Hearing aids are designed to improve sound perception, but users sometimes encounter a high-pitched squealing noise. This common occurrence is often a solvable problem. Understanding its causes can help address it effectively.
Understanding the Squeal
The squealing sound produced by a hearing aid is known as acoustic feedback. It occurs when amplified sound escapes the ear canal and is picked up again by the hearing aid’s microphone. This creates a continuous loop, re-amplified repeatedly, resulting in a distinct whistling or squealing noise. This mechanism is similar to when a microphone is held too close to a speaker, causing a loud, sustained screech.
While occasional feedback can occur when putting on or removing the device, persistent squealing indicates an underlying issue.
Common Reasons for Hearing Aid Squealing
One of the most common reasons is a poor fit of the hearing aid within the ear. If the earmold or dome does not create a proper seal, amplified sound can leak out and re-enter the microphone, causing feedback. Changes in ear shape over time, due to factors like weight changes, can also affect the snugness of the fit.
Another frequent cause is the presence of earwax buildup in the ear canal. If earwax obstructs the ear canal, it can block the sound from traveling properly, forcing it back towards the hearing aid’s microphone and initiating the feedback loop.
Operating the hearing aid at an excessively high volume can also induce squealing. When the volume is set too loud, the amplified sound may be more likely to leak out of the ear and be picked up by the microphone, creating feedback.
Physical obstructions near the hearing aid can also trigger feedback. Objects like hats, scarves, or even a hand placed over the ear can block the microphone or redirect amplified sound back into the device. Jaw movements, such as chewing or smiling, might temporarily affect the seal of the hearing aid, leading to momentary feedback.
Finally, internal issues with the hearing aid’s components can be a source of squealing. This might include a cracked or hardened tube connecting to the earmold, which can pull the earmold out of position, or a malfunctioning microphone or receiver. Mechanical problems such as dislodged microphones or issues with electrical contacts can also cause the device to squeal.
Practical Solutions and Prevention
Users should ensure the hearing aid is properly inserted and seated snugly in the ear canal. Gently repositioning the device can sometimes resolve feedback caused by an imperfect seal.
Regular ear hygiene and hearing aid cleaning are important preventive measures. Safely removing excessive earwax buildup from the ear canal can prevent sound from being blocked and reflected back into the device. Cleaning the hearing aid itself, including checking for wax or debris in the receiver and vents, helps maintain optimal function and prevents blockages.
Adjusting the hearing aid’s volume can also mitigate feedback. If the volume is set too high, lowering it slightly can reduce the likelihood of sound escaping and re-entering the microphone.
Being mindful of objects near the hearing aid can prevent feedback. Users should avoid placing hands, hats, or scarves directly over the hearing aid’s microphone or speaker. Ensuring the area around the device remains clear helps maintain proper sound flow.
When to Consult an Audiologist
If squealing persists despite attempting these practical solutions, or if the issue reappears consistently, it may be time to consult an audiologist. Persistent feedback could indicate a problem that requires professional assessment, such as an ill-fitting device due to changes in ear anatomy or a need for new earmolds.
An audiologist should also be consulted if there is visible damage to the hearing aid, such as a cracked casing or a stiff, discolored tube. They can assess internal components and perform necessary repairs or replacements. Similarly, if the squealing begins suddenly without an obvious cause, or if it is accompanied by ear discomfort or pain, professional evaluation is warranted. Audiologists can conduct thorough examinations and adjust the hearing aid’s programming or fit to resolve the issue.